This one is very touristic, being that you can catch a ferry from Manila to here and can have a luxury hotel stay on the island itself, but when I did a search nothing came up and I was surprised. They also have ghost tours!
https://en.wikipedia.org/wiki/Corregidor It's a famous WW2 battle site, USA vs Japan. Japan won.
"During the Battle of the Philippines (1941–42), the Imperial Japanese Army invaded Luzon from the north (at Lingayen Gulf) in early 1942 and attacked Manila from its landward side. American and Filipino troops under the command of General Douglas MacArthur, retreated to the Bataan Peninsula, west of Manila Bay. The fall of Bataan on April 9, 1942, ended all organized opposition by the U.S. Armed Forces in the Far East (USAFFE) and gave way to the invading Japanese forces in Luzon in the northern Philippines. They were forced to surrender due to the lack of food and ammunition, leaving Corregidor and its adjacent islets at Manila Bay as the only areas in the region under U.S. control.
Between December 24, 1941, and February 19, 1942, Corregidor was the temporary location for the Government of the Philippines" - e.g. the puppet government of the PH controlled by Japan.
I'll post some more about Bataan, including the power plant and death march in another post...
This one to me is just amazing, it's raw isn't it - same as back then a century ago to 80 years ago.
There are still many unexplored parts of the tunnel, japapnese bodies/americna bodies still lay in some places that were detonated on purpose to stop the advance. You "aren't" supposed to go into these tunnels as they are geotechnically unstable and can collapse anytime, but I was able to arrange scope some slightly with a guide that was experienced and there are exposed bones and more that won't be moved.
Most though are like this -